The polymeric membrane and polymeric adhesive of the invention are specially adapted for use with composite roof/roof deck assemblies comprising corrugated steel roof deck sections overlaid with optional insulation material and mineral board.
Notwithstanding the many advantages of such composite roof/roof deck assemblies, individuals using more conventional roofing/roof deck systems have encountered problems that can be avoided through the use of the invention disclosed herein. One problem relates to water that passes downward through cracks from the roof surface to the underlying roof deck material. The water passageways may be attributable to mistakes made by workers in applying the roof cover, or can be the result of long term weathering or wear on the roof surface, building movement, condensation, wind uplift or the like. Water leakage is a matter of particular concern with roofs having little or no slope, upon which water, ice or snow can accumulate. Prolonged contact between significant amounts of water and the roof membrane and, in turn, the underlying roof deck material can lead to their softening, thereby detrimentally affecting the strength and integrity of the roof deck/roofing system.
Problems have also been encountered with the leakage of asphalt, pitch or tar downward through cracks, crevices, or other imperfections in the conventional roof/roof deck assemblies. Still another problem relates to air leaks through the roof deck that may contribute to heat or air conditioning loss from the building interior as well as wind uplift damage. This circumstance is frequently seen where ballasted and mechanically anchored polymeric roof membranes are used.
U.S. Pat. No. 4,441,295 discloses a roofing installation wherein an elastomeric membrane is bonded to a rigid, membrane support board by means of a suitable bonding contact adhesive applied in a specific pattern. However, because elastomeric sheet material is typically coated with talc or other anti-blocking agent to prevent sticking during storage and shipment, problems have been encountered in using solvent based contact adhesives unless the anti-blocking agent is first cleaned from the elastomeric surface to be bonded. Other problems have arisen with solvent based contact adhesives because of their fast drying times and the resultant inability of installers to reposition sheets once they contact the underlying roof deck material.
Application Ser. No. 788,796 discloses an elastomeric membrane bonded by water-based polymeric adhesive to paper-faced gypsum sheathing to form a waterproof roof surface. The wind uplift force which the roof could withstand was somewhat limited by the internal strength of the paper facing material on the gypsum board.
To effectively deal with these problems, a means and method are therefore needed for easily and effectively adhering the roof membrane to the underlying roof deck materials of a composite roof deck/roofing assembly.